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控制文件使用详解

 
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一、Oracle 控制文件

        为二进制文件,初始化大小由CREATE DATABASE指定,可以使用RMAN备份

        记录了当前数据库的结构信息,同时也包含数据文件及日志文件的信息以及相关的状态,归档信息等等

        在参数文件中描述其位置,个数等等。通常采用分散放开,多路复用的原则。在mount阶段被读取,open阶段一直被使用

        维护数据库一致性(数据库启动时会比较控制文件与联机日志文件中的ckpt,即起始scn号,如相等则正常启动,否则需要介质恢复)

        一个控制文件只能属于一个数据库

        控制文件的任意修改将写入到初始化参数中指定的所有控制文件中,读取时则仅读取第一个控制文件

        控制文件只能连接一个数据库,控制文件的大小一般不要超过MB,最多为个,最少一个,互为镜像

              

        控制文件中包含的内容

            数据库的名字、ID、创建的时间戳

            表空间的名字

            联机日志文件、数据文件的位置、个数、名字

            联机日志的Sequence号码

            检查点的信息

            撤销段的开始或结束

            归档信息

            备份信息

  

二、查看控制文件的相关信息

    1.使用相关视图来查看

        V$CONTROLFILE                   --列出实例中所有控制文件的名字及状态信息

        V$PARAMETER                     --列出所有参数的位置及状态信息

        V$CONTROLFILE_RECORD_SECTION    --列出控制文件中记录的部分信息

        SHOW PARAMETER CONTROL_FILES    --列出控制文件的名字、状态、位置等



        SQL> select * from v$controlfile;

        STATUS  NAME                                               IS_ BLOCK_SIZE FILE_SIZE_BLKS

        ------- -------------------------------------------------- --- ---------- --------------

                /u01/app/oracle/oradata/orcl/control01.ctl         NO       16384            430

                /u01/app/oracle/oradata/orcl/control02.ctl         NO       16384            430

                /u01/app/oracle/oradata/orcl/control03.ctl         NO       16384            430

      

        SQL> select name,type,value from  v$parameter where name like '%control%';



        NAME                                 TYPE VALUE

        ------------------------------ ---------- ------------------------------------------------------------

        control_files                           2 /u01/app/oracle/oradata/orcl/control01.ctl, /u01/app/oracle/

                                                  oradata/orcl/control02.ctl, /u01/app/oracle/oradata/orcl/con

                                                  trol03.ctl

        control_file_record_keep_time           3 7

      

        SQL> select * from v$controlfile_record_section;

        TYPE                         RECORD_SIZE RECORDS_TOTAL RECORDS_USED FIRST_INDEX LAST_INDEX LAST_RECID

        ---------------------------- ----------- ------------- ------------ ----------- ---------- ----------

        DATABASE                             316             1            1           0          0          0

        CKPT PROGRESS                       8180            11            0           0          0          0

        REDO THREAD                          256             8            1           0          0          0

        REDO LOG                              72            16            9           0          0         20

        DATAFILE                             428           100            8           0          0         28

        FILENAME                             524          2298           21           0          0          0

        TABLESPACE                            68           100            7           0          0          7

        TEMPORARY FILENAME                    56           100            1           0          0          1

        RMAN CONFIGURATION                  1108            50            0           0          0          0

        LOG HISTORY                           56           292           35           1         35         35

        OFFLINE RANGE                        200           163            0           0          0          0



        TYPE                         RECORD_SIZE RECORDS_TOTAL RECORDS_USED FIRST_INDEX LAST_INDEX LAST_RECID

        ---------------------------- ----------- ------------- ------------ ----------- ---------- ----------

        ARCHIVED LOG                         584            28           20           1         20         20

        BACKUP SET                            40           409            0           0          0          0

        BACKUP PIECE                         736           200            0           0          0          0

        BACKUP DATAFILE                      116           282            0           0          0          0

        BACKUP REDOLOG                        76           215            0           0          0          0

        DATAFILE COPY                        660           223            1           1          1          1

        BACKUP CORRUPTION                     44           371            0           0          0          0

        COPY CORRUPTION                       40           409            0           0          0          0

        DELETED OBJECT                        20           818            3           1          3          3

        PROXY COPY                           852           249            0           0          0          0

        BACKUP SPFILE                         36           454            0           0          0          0



        TYPE                         RECORD_SIZE RECORDS_TOTAL RECORDS_USED FIRST_INDEX LAST_INDEX LAST_RECID

        ---------------------------- ----------- ------------- ------------ ----------- ---------- ----------

        DATABASE INCARNATION                  56           292            2           1          2          2

        FLASHBACK LOG                         84          2048            0           0          0          0

        RECOVERY DESTINATION                 180             1            1           0          0          0

        INSTANCE SPACE RESERVATION            28          1055            1           0          0          0

        REMOVABLE RECOVERY FILES              32          1000            0           0          0          0

        RMAN STATUS                          116           141            0           0          0          0

        THREAD INSTANCE NAME MAPPING          80             8            8           0          0          0

        MTTR                                 100             8            1           0          0          0

        DATAFILE HISTORY                     568            57            0           0          0          0

        STANDBY DATABASE MATRIX              400            10           10           0          0          0

        GUARANTEED RESTORE POINT             212          2048            0           0          0          0



        TYPE                         RECORD_SIZE RECORDS_TOTAL RECORDS_USED FIRST_INDEX LAST_INDEX LAST_RECID

        ---------------------------- ----------- ------------- ------------ ----------- ---------- ----------

        RESTORE POINT                        212          2083            0           0          0          0



        SQL> show parameter control_files;



        NAME                                 TYPE        VALUE

        ------------------------------------ ----------- ------------------------------

        control_files                        string      /u01/app/oracle/oradata/orcl/c

                                                         ontrol01.ctl, /u01/app/oracle/

                                                         oradata/orcl/control02.ctl, /u

                                                         01/app/oracle/oradata/orcl/con

                                                         trol03.ctl

        SQL> select controlfile_sequence# from v$database;



        CONTROLFILE_SEQUENCE#

        ---------------------

                          985     

                    

    2.使用STRINGS命令来查看控制文件中的具体内容

        SQL> host strings /u01/app/oracle/oradata/orcl/control01.ctl | more

        }|{z

        JORCL

        L-+RG

        +ORCL

        +ORCL

        orcl

        orcl

        -+-='

        -+-='

        /u01/app/oracle/oradata/orcl/redo03.log

        /u01/app/oracle/oradata/orcl/redo3.log

        /u01/app/oracle/oradata/orcl/redo02.log

        /u01/app/oracle/oradata/orcl/redo2.log

        /u01/app/oracle/oradata/orcl/redo01.log

        /u01/app/oracle/oradata/orcl/tbs1_2.dbf

        /u01/app/oracle/oradata/orcl/tbs1_1.dbf

        /u01/app/oracle/oradata/orcl/example01.dbf

        /u01/app/oracle/oradata/orcl/users01.dbf

        /u01/app/oracle/oradata/orcl/sysaux01.dbf

        /u01/app/oracle/oradata/orcl/undotbs01.dbf

        /u01/app/oracle/oradata/orcl/system01.dbf

        u01/app/oracle/oradata/orcl/undotbs02.dbf

        /u01/app/oracle/oradata/orcl/redo03.log

        /u01/app/oracle/oradata/orcl/redo3.log

        /u01/app/oracle/oradata/orcl/redo02.log

        /u01/app/oracle/oradata/orcl/redo2.log

        /u01/app/oracle/oradata/orcl/redo01.log

        /u01/app/oracle/oradata/orcl/tbs1_2.dbf

        /u01/app/oracle/oradata/orcl/tbs1_1.dbf

        /u01/app/oracle/oradata/orcl/example01.dbf

        /u01/app/oracle/oradata/orcl/users01.dbf

        /u01/app/oracle/oradata/orcl/sysaux01.dbf

        /u01/app/oracle/oradata/orcl/undotbs01.dbf

        /u01/app/oracle/oradata/orcl/system01.dbf

        u01/app/oracle/oradata/orcl/undotbs02.dbf

        SYSTEM

        UNDOTBS1

        SYSAUX

        USERS

        EXAMPLE

        TBS1

        TEMP

      

    3.备份控制文件到平面文件(然后查看控制文件中的具体内容)

      

        SQL> alter database backup controlfile  to trace as '/u01/app/oracle/ctl.txt';



        Database altered.

      

        --或者使用

        SQL> host strings /u01/app/oracle/oradata/orcl/control01.ctl > /u01/app/oracle/ctl.txt

      

        SQL> host cat /u01/app/oracle/ctl.txt; 

        -- The following are current System-scope REDO Log Archival related

        -- parameters and can be included in the database initialization file.

        --

        -- LOG_ARCHIVE_DEST=''

        -- LOG_ARCHIVE_DUPLEX_DEST=''

        --

        -- LOG_ARCHIVE_FORMAT=%t_%s_%r.dbf

        --

        -- DB_UNIQUE_NAME="orcl"

        --

        -- LOG_ARCHIVE_CONFIG='SEND, RECEIVE, NODG_CONFIG'

        -- LOG_ARCHIVE_MAX_PROCESSES=2

        -- STANDBY_FILE_MANAGEMENT=MANUAL

        -- STANDBY_ARCHIVE_DEST=?/dbs/arch

        -- FAL_CLIENT=''

        -- FAL_SERVER=''

        --

        -- LOG_ARCHIVE_DEST_10='LOCATION=USE_DB_RECOVERY_FILE_DEST'

        -- LOG_ARCHIVE_DEST_10='OPTIONAL REOPEN=300 NODELAY'

        -- LOG_ARCHIVE_DEST_10='ARCH NOAFFIRM NOEXPEDITE NOVERIFY SYNC'

        -- LOG_ARCHIVE_DEST_10='REGISTER NOALTERNATE NODEPENDENCY'

        -- LOG_ARCHIVE_DEST_10='NOMAX_FAILURE NOQUOTA_SIZE NOQUOTA_USED NODB_UNIQUE_NAME'

        -- LOG_ARCHIVE_DEST_10='VALID_FOR=(PRIMARY_ROLE,ONLINE_LOGFILES)'

        -- LOG_ARCHIVE_DEST_STATE_10=ENABLE

        --

        -- Below are two sets of SQL statements, each of which creates a new

        -- control file and uses it to open the database. The first set opens

        -- the database with the NORESETLOGS option and should be used only if

        -- the current versions of all online logs are available. The second

        -- set opens the database with the RESETLOGS option and should be used

        -- if online logs are unavailable.

        -- The appropriate set of statements can be copied from the trace into

        -- a script file, edited as necessary, and executed when there is a

        -- need to re-create the control file.

        --

        --     Set #1. NORESETLOGS case

        --

        -- The following commands will create a new control file and use it

        -- to open the database.

        -- Data used by Recovery Manager will be lost.

        -- Additional logs may be required for media recovery of offline

        -- Use this only if the current versions of all online logs are

        -- available.



        -- After mounting the created controlfile, the following SQL

        -- statement will place the database in the appropriate

        -- protection mode:

        --  ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE



        STARTUP NOMOUNT

        CREATE CONTROLFILE REUSE DATABASE "ORCL" NORESETLOGS  NOARCHIVELOG

            MAXLOGFILES 16

            MAXLOGMEMBERS 3

            MAXDATAFILES 100

            MAXINSTANCES 8

            MAXLOGHISTORY 292

        LOGFILE

          GROUP 1 '/u01/app/oracle/oradata/orcl/redo01.log'  SIZE 50M,

          GROUP 2 (

            '/u01/app/oracle/oradata/orcl/redo02.log',

            '/u01/app/oracle/oradata/orcl/redo2.log'

          ) SIZE 50M,

          GROUP 3 (

            '/u01/app/oracle/oradata/orcl/redo03.log',

            '/u01/app/oracle/oradata/orcl/redo3.log'

          ) SIZE 100M,

          GROUP 4 '/u01/app/oracle/oradata/orcl/redo04.log '  SIZE 50M,

          GROUP 7 (

            '/u01/app/oracle/oradata/orcl/redo07.log ',

            '/u01/app/oracle/oradata/orcl/redo7.log '

          ) SIZE 50M,

          GROUP 8 (

            '/u01/app/oracle/oradata/orcl/redo08.log',

            '/u01/app/oracle/oradata/orcl/redo8.log'

          ) SIZE 50M

        -- STANDBY LOGFILE



        DATAFILE

          '/u01/app/oracle/oradata/orcl/system01.dbf',

          '/u01/app/oracle/oradata/orcl/undotbs01.dbf',

          '/u01/app/oracle/oradata/orcl/sysaux01.dbf',

          '/u01/app/oracle/oradata/orcl/users01.dbf',

          '/u01/app/oracle/oradata/orcl/example01.dbf',

          '/u01/app/oracle/oradata/orcl/tbs1_1.dbf',

          '/u01/app/oracle/oradata/orcl/tbs1_2.dbf'

        CHARACTER SET WE8ISO8859P1

        ;



        -- Commands to re-create incarnation table

        -- Below log names MUST be changed to existing filenames on

        -- disk. Any one log file from each branch can be used to

        -- re-create incarnation records.

        -- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area

        --                                   /ORCL/archivelog/2010_05_20/o1_mf_1_1_%u_.arc';

        -- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area

        --                                   /ORCL/archivelog/2010_05_20/o1_mf_1_1_%u_.arc';

        -- Recovery is required if any of the datafiles are restored backups,

        -- or if the last shutdown was not normal or immediate.

        RECOVER DATABASE



        -- Database can now be opened normally.

        ALTER DATABASE OPEN;



        -- Commands to add tempfiles to temporary tablespaces.

        -- Online tempfiles have complete space information.

        -- Other tempfiles may require adjustment.

        ALTER TABLESPACE TEMP ADD TEMPFILE '/u01/app/oracle/oradata/orcl/temp01.dbf'

             SIZE 26214400  REUSE AUTOEXTEND ON NEXT 655360  MAXSIZE 32767M;

        -- End of tempfile additions.

        --

        --     Set #2. RESETLOGS case

        --

        -- The following commands will create a new control file and use it

        -- to open the database.

        -- Data used by Recovery Manager will be lost.

        -- The contents of online logs will be lost and all backups will

        -- be invalidated. Use this only if online logs are damaged.



        -- After mounting the created controlfile, the following SQL

        -- statement will place the database in the appropriate

        -- protection mode:

        --  ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE



        STARTUP NOMOUNT

        CREATE CONTROLFILE REUSE DATABASE "ORCL" RESETLOGS  NOARCHIVELOG

            MAXLOGFILES 16

            MAXLOGMEMBERS 3

            MAXDATAFILES 100

            MAXINSTANCES 8

            MAXLOGHISTORY 292

        LOGFILE

          GROUP 1 '/u01/app/oracle/oradata/orcl/redo01.log'  SIZE 50M,

          GROUP 2 (

            '/u01/app/oracle/oradata/orcl/redo02.log',

            '/u01/app/oracle/oradata/orcl/redo2.log'

          ) SIZE 50M,

          GROUP 3 (

            '/u01/app/oracle/oradata/orcl/redo03.log',

            '/u01/app/oracle/oradata/orcl/redo3.log'

          ) SIZE 100M,

          GROUP 4 '/u01/app/oracle/oradata/orcl/redo04.log '  SIZE 50M,

          GROUP 7 (

            '/u01/app/oracle/oradata/orcl/redo07.log ',

            '/u01/app/oracle/oradata/orcl/redo7.log '

          ) SIZE 50M,

          GROUP 8 (

            '/u01/app/oracle/oradata/orcl/redo08.log',

            '/u01/app/oracle/oradata/orcl/redo8.log'

          ) SIZE 50M

        -- STANDBY LOGFILE



        DATAFILE

          '/u01/app/oracle/oradata/orcl/system01.dbf',

          '/u01/app/oracle/oradata/orcl/undotbs01.dbf',

          '/u01/app/oracle/oradata/orcl/sysaux01.dbf',

          '/u01/app/oracle/oradata/orcl/users01.dbf',

          '/u01/app/oracle/oradata/orcl/example01.dbf',

          '/u01/app/oracle/oradata/orcl/tbs1_1.dbf',

          '/u01/app/oracle/oradata/orcl/tbs1_2.dbf'

        CHARACTER SET WE8ISO8859P1

        ;



        -- Commands to re-create incarnation table

        -- Below log names MUST be changed to existing filenames on

        -- disk. Any one log file from each branch can be used to

        -- re-create incarnation records.

        -- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area

        --                                   /ORCL/archivelog/2010_05_20/o1_mf_1_1_%u_.arc';

        -- ALTER DATABASE REGISTER LOGFILE '/u01/app/oracle/flash_recovery_area

        --                                    /ORCL/archivelog/2010_05_20/o1_mf_1_1_%u_.arc';

        -- Recovery is required if any of the datafiles are restored backups,

        -- or if the last shutdown was not normal or immediate.

        RECOVER DATABASE USING BACKUP CONTROLFILE



        -- Database can now be opened zeroing the online logs.

        ALTER DATABASE OPEN RESETLOGS;



        -- Commands to add tempfiles to temporary tablespaces.

        -- Online tempfiles have complete space information.

        -- Other tempfiles may require adjustment.

        ALTER TABLESPACE TEMP ADD TEMPFILE '/u01/app/oracle/oradata/orcl/temp01.dbf'

             SIZE 26214400  REUSE AUTOEXTEND ON NEXT 655360  MAXSIZE 32767M;

        -- End of tempfile additions.

  

    4.转储控制文件内容(查看控制文件中的具体内容)

        alter session set events 'immediate trace name CONTROLF level 12'; level表示级别

        或                     --level1  块头的内容 --level2 数据文件内容 --levle 10 |12 所有内容

        oradebug setmypid

        oradebug dump controlf 12

  

        SQL> alter system set events 'immediate trace name controlf level 10';



        System altered.



        SQL> show parameter user_dump;



        NAME                                 TYPE        VALUE

        ------------------------------------ ----------- ------------------------------

        user_dump_dest                       string      /u01/app/oracle/admin/orcl/udu

                                                         mp

      

        --查看路径中最新的文件

        [root@robinson ~]# vim /u01/app/oracle/admin/orcl/udump/orcl_ora_5110.trc

      

        --以下仅列出部分信息

        Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production

        With the Partitioning, OLAP and Data Mining options

        ORACLE_HOME = /u01/app/oracle/10g

        System name:    Linux

        Node name:      robinson.com

        Release:        2.6.18-164.el5xen

        Version:        #1 SMP Tue Aug 18 16:06:30 EDT 2009

        Machine:        i686

        Instance name: orcl

        Redo thread mounted by this instance: 1

        Oracle process number: 19

        Unix process pid: 5110, image: oracle@robinson.com (TNS V1-V3)



        *** 2010-05-20 18:52:30.104

        *** SERVICE NAME:(SYS$USERS) 2010-05-20 18:52:30.084

        *** SESSION ID:(159.10) 2010-05-20 18:52:30.084

        DUMP OF CONTROL FILES, Seq # 985 = 0x3d9

         V10 STYLE FILE HEADER:

                Compatibility Vsn = 169869568=0xa200100

                Db ID=1242732291=0x4a129703, Db Name='ORCL'

                Activation ID=0=0x0

                Control Seq=985=0x3d9, File size=430=0x1ae

                File Number=0, Blksiz=16384, File Type=1 CONTROL

         Logical block number 1 (header block)

        Dump of memory from 0xB7EF7E00 to 0xB7EFBE00

          

        --使用oradebug setmypid

        SQL> oradebug setmypid  --标记当前进程

        Statement processed.

        --获得当前的spid

        SQL> select spid from v$process where addr =

          2      (select paddr from v$session where sid =

          3          (select sid from v$mystat where rownum = 1));



        SPID

        ------------

        5110

      

        SQL> oradebug dump controlf 3;--3表示包含头文件和数据文件内容

        Statement processed.

      

        --查看user_dump_dest  路径

        SQL> show parameter user_d 



        NAME                                 TYPE        VALUE

        ------------------------------------ ----------- ------------------------------

        user_dump_dest                       string      /u01/app/oracle/admin/orcl/udu

                                                         mp

      

        --找到当前spid的trc文件                                           

        SQL>  ! ls /u01/app/oracle/admin/orcl/udump/*5110.*              --  */

        /u01/app/oracle/admin/orcl/udump/orcl_ora_5110.trc

        SQL>  ! cat /u01/app/oracle/admin/orcl/udump/orcl_ora_5110.trc

      

        --下面列出的为部分内容

        ***************************************************************************

        RMAN CONFIGURATION RECORDS

        ***************************************************************************

         (size = 1108, compat size = 1108, section max = 50, section in-use = 0,

          last-recid= 0, old-recno = 0, last-recno = 0)

         (extent = 1, blkno = 90, numrecs = 50)

         ***************************************************************************

        FLASHBACK LOGFILE RECORDS

        ***************************************************************************

         (size = 84, compat size = 84, section max = 2048, section in-use = 0,

          last-recid= 0, old-recno = 0, last-recno = 0)

         (extent = 1, blkno = 139, numrecs = 2048)

                

        ***************************************************************************

        THREAD INSTANCE MAPPING RECORDS

        ***************************************************************************

         (size = 80, compat size = 80, section max = 8, section in-use = 8,

          last-recid= 0, old-recno = 0, last-recno = 0)

         (extent = 1, blkno = 156, numrecs =

        orcl recno=1

        UNNAMED_INSTANCE_2 recno=2

        UNNAMED_INSTANCE_3 recno=3

        UNNAMED_INSTANCE_4 recno=4

        UNNAMED_INSTANCE_5 recno=5

        UNNAMED_INSTANCE_6 recno=6

        UNNAMED_INSTANCE_7 recno=7

        UNNAMED_INSTANCE_8 recno=8

         

        ***************************************************************************

        MTTR RECORDS

        ***************************************************************************

         (size = 100, compat size = 100, section max = 8, section in-use = 1,

          last-recid= 0, old-recno = 0, last-recno = 0)

         (extent = 1, blkno = 157, numrecs =

        MTTR record for thread 1

        MTTR statistics status: 3

        Init time: Avg: 47090974 us, Times measured: 4

        File open time: Avg: 11225 us, Times measured: 21

        Log block read time: Avg: 20 us, Times measured: 65536

        Data block read/claim time: Avg: 170 us, Times measured: 1000

        Data block write time: Avg: 390 us

        1000 change vector apply time: Avg: 112435 us, Times measured: 37

        Ratio Information:

        # of log blocks measured: 207891

        # of data blocks measured: 12536

        # of change vectors measured: 564444

               

        ***************************************************************************

        STANDBY DATABASE MAP RECORDS

        ***************************************************************************

         (size = 400, compat size = 400, section max = 10, section in-use = 10,

          last-recid= 0, old-recno = 0, last-recno = 0)

         (extent = 1, blkno = 160, numrecs = 10)

                

        ***************************************************************************

        RESTORE POINT RECORDS

        ***************************************************************************

         (size = 212, compat size = 212, section max = 2048, section in-use = 0,

          last-recid= 0, old-recno = 0, last-recno = 0)

         (extent = 1, blkno = 161, numrecs = 2048)

  

三、控制文件的管理

    规划原则:多路复用,建议存放到不同的磁盘或同一磁盘不同的分区

    个数与位置及状态管理:

        查看控制文件的状态是否与参数定义中的相吻合,当数据库发生结构修改时,将修改内容同时写入控制文件

    备份管理

    恢复管理

    新建控制文件语句

  

    spfile或pfile都可以实现对控制文件的个数及位置管理

    spfile步骤

        修改spfile参数中的control_files   -- alter system ... scope = spfile | both |memory

        一致性关闭数据库

        增加或减少控制文件(cp or mv)

        启动数据库使用spfile

        验证结果

      

    pfile步骤

        一致性关闭数据库

        修改pfile参数(vi或vim)   修改*.control_files=......这一段

        增加或减少控制文件(cp or mv)

        启动数据库使用pfile

        验证结果

      

    --演示spfile修改控制文件

        SQL> show parameter control_file



        NAME                                 TYPE        VALUE

        ------------------------------------ ----------- ------------------------------

        control_file_record_keep_time        integer     7

        control_files                        string      /u01/app/oracle/oradata/orcl/c

                                                         ontrol01.ctl, /u01/app/oracle/

                                                         oradata/orcl/control02.ctl, /u

                                                         01/app/oracle/oradata/orcl/con

                                                         trol03.ctl

        --将控制文件减少到一个

        SQL> alter system set control_files = '/u01/app/oracle/oradata/orcl/control01.ctl' scope = spfile;



        System altered.



        SQL> shutdown immediate;

        Database closed.

        Database dismounted.

        ORACLE instance shut down.

        SQL> startup mount

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              88082196 bytes

        Database Buffers          159383552 bytes

        Redo Buffers                2973696 bytes

        Database mounted.

      

        --再次查看参数文件,已显示为一个

        SQL> show parameter control_file



        NAME                                 TYPE        VALUE

        ------------------------------------ ----------- ------------------------------

        control_file_record_keep_time        integer     7

        control_files                        string      /u01/app/oracle/oradata/orcl/c

                                                         ontrol01.ctl

      

        --增加控制文件(在nomount状态下即可修改)

        SQL> alter system set control_files = '/u01/app/oracle/oradata/orcl/control01.ctl',

          2  '/u01/app/oracle/oradata/orcl/control02.ctl',

          3  '/u01/app/oracle/oradata/orcl/control03.ctl'

          4  scope = spfile;



        System altered.

      

        --启动时可以看到在实例阶段出现了版本号不一致的问题

        SQL> startup force

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              88082196 bytes

        Database Buffers          159383552 bytes

        Redo Buffers                2973696 bytes

        ORA-00214: control file '/u01/app/oracle/oradata/orcl/control01.ctl' version

        1051 inconsistent with file '/u01/app/oracle/oradata/orcl/control02.ctl'

        version 1049

      

        --处理办法,用版本号高的控制文件覆盖版本号低的控制文件

        SQL> host cp /u01/app/oracle/oradata/orcl/control01.ctl /u01/app/oracle/oradata/orcl/control02.ctl;



        SQL> host cp /u01/app/oracle/oradata/orcl/control01.ctl /u01/app/oracle/oradata/orcl/control03.ctl;



        SQL> alter database mount;



        Database altered.



        SQL> alter database open;



        Database altered. 

      

    对于控制文件丢失的情况下,通过查看参数文件中设置,使用操作系统命令逐个查看这些文件是否存在

  

        SQL> host ls /u01/app/oracle/oradata/orcl/control01.ctl

        /u01/app/oracle/oradata/orcl/control01.ctl



        SQL> host ls /u01/app/oracle/oradata/orcl/control02.ctl

        /u01/app/oracle/oradata/orcl/control02.ctl

  

    查看控制文件所在的目录可用空间及控制文件的大小,建议不要超过100MB

        SQL> host ls /u01/app/oracle/oradata/orcl/c*.ctl -lh

        -rw-r----- 1 oracle oinstall 6.8M May 23 10:55 /u01/app/oracle/oradata/orcl/control01.ctl

        -rw-r----- 1 oracle oinstall 6.8M May 23 10:55 /u01/app/oracle/oradata/orcl/control02.ctl

        -rw-r----- 1 oracle oinstall 6.8M May 23 10:55 /u01/app/oracle/oradata/orcl/control03.ctl



        SQL> ! df -h

        Filesystem            Size  Used Avail Use% Mounted on

        /dev/sda2             6.4G  3.9G  2.2G  64% /

        /dev/sdd1             6.8G  3.7G  2.8G  58% /u01

        /dev/sdc2             1.2G   34M  1.1G   3% /home

        /dev/sdc1             760M   17M  704M   3% /tmp

        /dev/sda1             456M   18M  415M   5% /boot

        tmpfs                 450M     0  450M   0% /dev/shm

        none                  450M  104K  450M   1% /var/lib/xenstored

      

    控制文件的备份

        热备:

            alter database backup controlfile to '<dir>';  --热备份控制文件

            alter database backup controlfile to trace as '<dir>' ;--得到建立控制文件的脚本

        RMAN:

            backup current controlfile;

            backup database include current controlfile;

            -- 或者设置RMAN 为自动备份

            RMAN > configure controlfile autobackup on;

          

        --演示备份

        --用于归档模式下的恢复,直接覆盖到控制文件

        SQL> alter database backup controlfile to '/u01/app/oracle/control.bak';



        Database altered.

      

        --用于重建控制文件

        SQL> alter database backup controlfile to trace as '/u01/app/oracle/recreate_controlfile.txt';



        Database altered.

     

        --使用RMAN备份

        RMAN> connect target /;



        connected to target database: ORCL (DBID=1242732291)



        RMAN> backup current controlfile;   --handle为备份文件的路径



        Starting backup at 23-MAY-10

        using target database control file instead of recovery catalog

        allocated channel: ORA_DISK_1

        channel ORA_DISK_1: sid=148 devtype=DISK

        channel ORA_DISK_1: starting full datafile backupset

        channel ORA_DISK_1: specifying datafile(s) in backupset

        including current control file in backupset

        channel ORA_DISK_1: starting piece 1 at 23-MAY-10

        channel ORA_DISK_1: finished piece 1 at 23-MAY-10

        piece handle=/u01/app/oracle/flash_recovery_area/ORCL/backupset/

              2010_05_23/o1_mf_ncnnf_TAG20100523T131841_5zkgon2l_.bkp tag=TAG20100523T131841 comment=NONE

        channel ORA_DISK_1: backup set complete, elapsed time: 00:00:05

        Finished backup at 23-MAY-10

      

        RMAN> backup database include current controlfile;



        Starting backup at 23-MAY-10

        using target database control file instead of recovery catalog

        allocated channel: ORA_DISK_1

        channel ORA_DISK_1: sid=141 devtype=DISK

        channel ORA_DISK_1: starting full datafile backupset

        channel ORA_DISK_1: specifying datafile(s) in backupset

        input datafile fno=00001 name=/u01/app/oracle/oradata/orcl/system01.dbf

        input datafile fno=00003 name=/u01/app/oracle/oradata/orcl/sysaux01.dbf

        input datafile fno=00005 name=/u01/app/oracle/oradata/orcl/example01.dbf

        input datafile fno=00006 name=/u01/app/oracle/oradata/orcl/tbs1_1.dbf

        input datafile fno=00007 name=/u01/app/oracle/oradata/orcl/tbs1_2.dbf

        input datafile fno=00002 name=/u01/app/oracle/oradata/orcl/undotbs01.dbf

        input datafile fno=00004 name=/u01/app/oracle/oradata/orcl/users01.dbf

        channel ORA_DISK_1: starting piece 1 at 23-MAY-10

        channel ORA_DISK_1: finished piece 1 at 23-MAY-10

        piece handle=/u01/app/oracle/flash_recovery_area/ORCL/backupset/

              2010_05_23/o1_mf_nnndf_TAG20100523T132647_5zkh4sk2_.bkp tag=TAG20100523T132647 comment=NONE

        channel ORA_DISK_1: backup set complete, elapsed time: 00:05:25

        channel ORA_DISK_1: starting full datafile backupset

        channel ORA_DISK_1: specifying datafile(s) in backupset

        including current control file in backupset

        including current SPFILE in backupset

        channel ORA_DISK_1: starting piece 1 at 23-MAY-10

        channel ORA_DISK_1: finished piece 1 at 23-MAY-10

        piece handle=/u01/app/oracle/flash_recovery_area/ORCL/backupset/

              2010_05_23/o1_mf_ncsnf_TAG20100523T132647_5zkhh5st_.bkp tag=TAG20100523T132647 comment=NONE

        channel ORA_DISK_1: backup set complete, elapsed time: 00:00:14

        Finished backup at 23-MAY-10

      

        RMAN> show all;



        RMAN configuration parameters are:

        CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default

        CONFIGURE BACKUP OPTIMIZATION OFF; # default

        CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default

        CONFIGURE CONTROLFILE AUTOBACKUP OFF; # default

        CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default

        CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default

        CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default

        CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default

        CONFIGURE MAXSETSIZE TO UNLIMITED; # default

        CONFIGURE ENCRYPTION FOR DATABASE OFF; # default

        CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default

        CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default

        CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/u01/app/oracle/10g/dbs/snapcf_orcl.f'; # default



        RMAN> configure controlfile autobackup on;   --将控制文件自动备份功能置为on;



        new RMAN configuration parameters:

        CONFIGURE CONTROLFILE AUTOBACKUP ON;

        new RMAN configuration parameters are successfully stored

      

    控制文件的恢复管理

        控制文件版本不一致的问题

            用较新版本的控制文件覆盖旧版本的控制文件

            直接修改参数control_file

        丢失问题

            归档模式下

                当归档日志全的时候,先做全备,然后使用备份的控制文件恢复即可

                当归档日志不全的时候,先做全备,然后建立新的控制文件即可

            非归档模式下

                先做全备,然后建立新的控制文件即可

        新建控制文件语句

            数据库处于mount及open状态

            执行alter database backup controlfile to trace as '<dir>';得到建立语句

            注意[no]archievelog [no]resetlogs 两个参数的区别

          

    版本不一致演示

        SQL> startup

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              88082196 bytes

        Database Buffers          159383552 bytes

        Redo Buffers                2973696 bytes

        ORA-00214: control file '/u01/app/oracle/oradata/orcl/control01.ctl' version

        1051 inconsistent with file '/u01/app/oracle/oradata/orcl/control02.ctl'

        version 1049

      

        --处理办法,用版本号高的控制文件覆盖版本号低的控制文件

        SQL> host cp /u01/app/oracle/oradata/orcl/control01.ctl /u01/app/oracle/oradata/orcl/control02.ctl;



        SQL> host cp /u01/app/oracle/oradata/orcl/control01.ctl /u01/app/oracle/oradata/orcl/control03.ctl;



        SQL> alter database mount;



        Database altered.



        SQL> alter database open;



        Database altered. 

      

        --控制文件部分丢失的演示,原本有两个控制文件,丢失一个

        --处理办法:

            1.将存在的控制文件复制到目的路径并更改控制文件名字为正确的控制文件名称

            2.修改控控文件参数将丢失的控制文件去掉(一般不建议使用)

        SQL> alter system set control_files = ' /u01/app/oracle/oradata/orcl/c ontrol01.ctl',

          2  '/u01/app/oracle/oradata/orcl/control02.ctl' scope = spfile;



        System altered.



        SQL> shutdown immediate;

        Database closed.

        Database dismounted.

        ORACLE instance shut down.

        SQL> startup

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              75499284 bytes

        Database Buffers          171966464 bytes

        Redo Buffers                2973696 bytes

        ORA-00205: error in identifying control file, check alert log for more info

              

        [oracle@robinson ~]$ tail -n 100 /u01/app/oracle/admin/orcl/bdump/alert_orcl.log

        ..........................    

        Tue Jun  8 19:03:42 2010

        starting up 1 shared server(s) ...

        MMON started with pid=11, OS id=4557

        CJQ0 started with pid=10, OS id=4555

        Tue Jun  8 19:03:44 2010

        ALTER DATABASE   MOUNT

        Tue Jun  8 19:03:44 2010

        ORA-00202: control file: '/u01/app/oracle/10g/dbs/ /u01/app/oracle/oradata/orcl/c ontrol01.ctl'

        ORA-27037: unable to obtain file status

        Linux Error: 2: No such file or directory

        Additional information: 3

        Tue Jun  8 19:03:47 2010

        ORA-205 signalled during: ALTER DATABASE   MOUNT...



        --从警告日志中得知,文件名为c ontrol01.ctl的文件不存在,故将其改为正确的文件名

                                                       

        SQL> alter system set control_files='/u01/app/oracle/oradata/orcl/control01.ctl',

          2  '/u01/app/oracle/oradata/orcl/control02.ctl' scope = spfile;



        System altered.



        SQL> startup force

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              83887892 bytes

        Database Buffers          163577856 bytes

        Redo Buffers                2973696 bytes

        Database mounted.

        Database opened.



    非归档模式下,当所有的控制文件都丢失,只能重建控制文件来解决



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              79693588 bytes

        Database Buffers          167772160 bytes

        Redo Buffers                2973696 bytes

        ORA-00205: error in identifying control file, check alert log for more info

      

        [oracle@robinson ~]$tail -n 100 /u01/app/oracle/admin/orcl/bdump/alert_orcl.log

        ALTER DATABASE   MOUNT

        Thu Jul 15 12:13:15 2010

        ORA-00202: control file: '/u01/app/oracle/oradata/orcl/control01.ctl'

        ORA-27037: unable to obtain file status

        Linux Error: 2: No such file or directory



        --重建控制文件主要有三个需要考虑的是

        --搞清各个日志文件的大小及位置

        --搞清各个数据文件的位置

        --设置正确的字符集    



        SQL> CREATE CONTROLFILE REUSE DATABASE "orcl" NOARCHIVELOG NORESTLOGS

          2  MAXLOGFILES 16

          3  MAXLOGMEMBER 3

          4  MAXDATAFILES 20

          5  MAXINSTANCES 8

          6  MAXLOGHISTORY 3

          7  LOGFILE

          8    GROUP 1(

          9      'u01/app/oracle/oradata/orcl/redo1.log',

         10      '/u01/app/oracle/oradata/orcl/redo01.log'

         11       ) SIZE 50M,

         12    GROUP 2(

         13      '/u01/app/oracle/oradata/orcl/redo2.log', 

         14      '/u01/app/oracle/oradata/orcl/redo02.log'     

         15       ) SIZE 50M,

         16    GROUP 3(

         17      '/u01/app/oracle/oradata/orcl/redo3.log',     

         18      '/u01/app/oracle/oradata/orcl/redo03.log'   

         19       ) SIZE 100M

         20  DATAFILE

         21    '/u01/app/oracle/oradata/orcl/tbs1_2.dbf',

         22    '/u01/app/oracle/oradata/orcl/tbs1_1.dbf',    

         23    '/u01/app/oracle/oradata/orcl/example01.dbf',

         24    '/u01/app/oracle/oradata/orcl/users01.dbf',

         25    '/u01/app/oracle/oradata/orcl/sysaux01.dbf',

         26    '/u01/app/oracle/oradata/orcl/system01.dbf',

         27    '/u01/app/oracle/oradata/orcl/undotbs01.dbf'

         28  CHARACTER SET WE8ISO8859P1;

        CREATE CONTROLFILE REUSE DATABASE "orcl" NOARCHIVELOG NORESTLOGS

                                                              *

        ERROR at line 1:

        ORA-01967: invalid option for CREATE CONTROLFILE



        SQL> save /u01/app/oracle/oradata/rectl.sql;

        Created file /u01/app/oracle/oradata/rectl.sql

        SQL> ho vim /u01/app/oracle/oradata/rectl.sql



        SQL> @/u01/app/oracle/oradata/rectl.sql



        Control file created.



        --下面给出正确执行后的语句内容

        SQL> host cat /u01/app/oracle/oradata/rectl.sql

        CREATE CONTROLFILE REUSE DATABASE "orcl" NOARCHIVELOG NORESETLOGS

        MAXLOGFILES 16

        MAXLOGMEMBERS 3

        MAXDATAFILES 20

        MAXINSTANCES 8

        MAXLOGHISTORY 3

        LOGFILE

          GROUP 1(

            '/u01/app/oracle/oradata/orcl/redo01.log'

             ) SIZE 50M,

          GROUP 2(

            '/u01/app/oracle/oradata/orcl/redo2.log',

            '/u01/app/oracle/oradata/orcl/redo02.log'

             ) SIZE 50M,

          GROUP 3(

            '/u01/app/oracle/oradata/orcl/redo3.log',

            '/u01/app/oracle/oradata/orcl/redo03.log'

             ) SIZE 100M

        DATAFILE

          '/u01/app/oracle/oradata/orcl/tbs1_2.dbf',

          '/u01/app/oracle/oradata/orcl/tbs1_1.dbf',

          '/u01/app/oracle/oradata/orcl/example01.dbf',

          '/u01/app/oracle/oradata/orcl/users01.dbf',

          '/u01/app/oracle/oradata/orcl/sysaux01.dbf',

          '/u01/app/oracle/oradata/orcl/system01.dbf',

          '/u01/app/oracle/oradata/orcl/undotbs01.dbf'

        CHARACTER SET WE8ISO8859P1

        /

      

        --将数据库切换到open 状态

        SQL> alter database open;



        Database altered.



        SQL> select * from dual;



        D

        -

        X

      

        --查看已经新产生了控制文件

        SQL> host ls $ORACLE_BASE/oradata/orcl/control* -l  --可以看到新增了控制文件control01.ctl和control02.ctl

        -rw-r----- 1 oracle oinstall 6012928 Jul 15 12:58 /u01/app/oracle/oradata/orcl/control01.ctl

        -rw------- 1 oracle oinstall 7389184 Jul 15 12:04 /u01/app/oracle/oradata/orcl/control01.ctl.bak

        -rw-r----- 1 oracle oinstall 6012928 Jul 15 12:58 /u01/app/oracle/oradata/orcl/control02.ctl



    归档模式下控制文件全部丢失的处理

        --首先将数据库切换到归档模式

        SQL> shutdown immediate;

        Database closed.

        Database dismounted.

        ORACLE instance shut down.

        SQL> startup mount;

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              79693588 bytes

        Database Buffers          167772160 bytes

        Redo Buffers                2973696 bytes

        Database mounted.

        SQL> alter database archivelog;

        Database altered.



        SQL> alter database open  ;

        Database altered.



        --查看归档的状态

        SQL> archive log list;

        Database log mode              Archive Mode

        Automatic archival             Enabled

        Archive destination            USE_DB_RECOVERY_FILE_DEST

        Oldest online log sequence     1

        Next log sequence to archive   3

        Current log sequence           3



        --备份控制文件

        SQL> alter database backup controlfile to '/u01/app/oracle/oradata/orcl/rectl.bak';



        Database altered.



        SQL> create table tb_temp(id int,col1 varchar2(20));



        Table created.



        SQL> insert into tb_temp select 1,'Robinson' from dual;



        1 row created.



        SQL> commit;



        Commit complete.



        SQL> alter system switch logfile;   --切换日志



        System altered.



        SQL> archive log list; --日志切换后sequence由变成

        Database log mode              Archive Mode

        Automatic archival             Enabled

        Archive destination            USE_DB_RECOVERY_FILE_DEST

        Oldest online log sequence     2

        Next log sequence to archive   4

        Current log sequence           4



        --模拟控制文件全部丢失

        SQL> startup

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              79693588 bytes

        Database Buffers          167772160 bytes

        Redo Buffers                2973696 bytes

        ORA-00205: error in identifying control file, check alert log for more info



        SQL> show parameter control



        NAME                                 TYPE        VALUE

        ------------------------------------ ----------- ------------------------------

        control_file_record_keep_time        integer     7

        control_files                        string      /u01/app/oracle/oradata/orcl/c

                                                         ontrol01.ctl, /u01/app/oracle/

                                                         oradata/orcl/control02.ctl



        --查看物理控制文件是否存在                                            

        SQL> ho ls /u01/app/oracle/oradata/orcl/contr*

        ls: /u01/app/oracle/oradata/orcl/contr*: No such file or directory



        --建议先对数据库作备份再将备份的控制文件复制到参数文件中指定的位置



        SQL> ho cp /u01/app/oracle/oradata/orcl/rectl.bak /u01/app/oracle/oradata/orcl/control01.ctl



        SQL> ho cp /u01/app/oracle/oradata/orcl/rectl.bak /u01/app/oracle/oradata/orcl/control02.ctl



        SQL> alter database mount;



        Database altered.



        SQL> alter database open;

        alter database open

        *

        ERROR at line 1:

        ORA-01589: must use RESETLOGS or NORESETLOGS option for database open



        SQL> shutdown immediate;

        ORA-01109: database not open

        Database dismounted.

        ORACLE instance shut down.

      

        SQL> startup mount;

        ORACLE instance started.



        Total System Global Area  251658240 bytes

        Fixed Size                  1218796 bytes

        Variable Size              79693588 bytes

        Database Buffers          167772160 bytes

        Redo Buffers                2973696 bytes

        Database mounted.



        SQL> alter database open resetlogs;



        Database altered.



        SQL> select * from dual;



        D

        -

        X



        SQL> select * from tb_temp;  --表成功被恢复



                ID COL1

        ---------- --------------------

                 1 Robinson



        SQL> drop table tb_temp purge;



        Table dropped.



        SQL> archive log list;   --日志的sequence号被置为

        Database log mode              Archive Mode

        Automatic archival             Enabled

        Archive destination            USE_DB_RECOVERY_FILE_DEST

        Oldest online log sequence     1

        Next log sequence to archive   1

        Current log sequence           1
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